U.S. Pat. Nos. 5,621,924, 6,618,866, and 6,782,563, the disclosures all of which are herein incorporated by reference, disclose a vacuum tank construction for use with a vacuum toilet assembly that have a number of advantages over the prior art. While the vacuum tank of the present invention functions primarily in the same manner as the vacuum tanks disclosed in the above mentioned patents the construction of the present invention has several features that provide a number of advantages over these patents.
For example, the construction according to the present invention is more compact both vertically and horizontally than the vacuum tanks disclosed in the above patents thus permitting mounting in more compact areas. Further, the vacuum tank construction according to the present invention incorporates a two-piece tank design for ease of maintenance. The vacuum tank construction according to the present invention also incorporates an integrated dip tube design that increases the performance of a vacuum pump and reduces tolerances associated with the dip tube assemblies of the above patents. Conventional dip tubes, as described in the above patents, are mechanically attached to the vacuum tank by a method known in the art such as screwing, gluing, etc. and may shift over time thus creating leaks in the joints and thus decreasing the pumping efficiency of the vacuum pump. In addition, the shifting of the dip tube may reduce the gap between the opening at the bottom of the dip tube and the bottom of the vacuum tank and thus may create plugging possibilities.
It is the primary object of the present invention to provide a compact vacuum tank having the same or improved functionality as conventional vacuum tanks, and a desirable dip tube assembly for use therewith. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.